Pioneer SX-20-K Service Manual page 20

1
FL No light
A
[Product state]
• Power cord connection (230 V/50 Hz)
• Unit POWER SW: ON
• Power ON operation by remote control
FL does not light.
Does a sound come
out from SACD/CD input?
B
Yes
Is there AC waveform
signal in FLT pin 1/pin 39?
(Check the FRONT Assy side B.)
Yes
Is there DC-30V in
C
FRONT Assy -30V?
(Check the FPC400 pin 1
on FRONT Assy side B.)
Yes
Is there communication waveform in
FRONT Assy FL_CLK, FL_DOUT?
(Check the FL_CLK, FL_DOUT
on FRONT Assy side B.)
Yes
D
Is there DC+3.3V in
IC400 VDD?
(Check the VDD on
FRONT Assy side B.)
Yes
E
Is there communication
waveform signal in
FLT pin 4 - pin 36?
(Check the FRONT Assy side B.)
Yes
FLT400 is defective or its solder is
defective.
F
20
1
2
• SPEAKER-A selection
• INPUT: SACD/CD
No
I
See "Speaker_A No Sound".
Is there AC waveform
No
signal in R400A/R403A?
(Check the FRONT Assy side B.)
Yes
• R400A or R403A is defective or its solder is defective.
• R404 or R405 is defective or its solder is defective.
• DZ400 is defective or its solder is defective.
Is there DC-30V
No
in MAIN Assy -30V?
(Check the J304.)
Yes
• FPC101 or FPC400 solder is defective.
• Connection between FPC101 - FPC400 is defective.
Is there communication waveform
No
in MAIN Assy FL_CLK, FL_DOUT?
(Check the FPC101 pin 9/pin 10.)
Yes
• FPC101 or FPC400 solder is defective.
• Connection between FPC101 - FPC400 is defective.
Is there DC+3.3V in
No
FRONT Assy FL_SW/RLY?
(Check the FPC400 pin 15 on
FRONT Assy side B.)
Yes
Does the STADBY LED
(Red) light at standby state?
Yes
• Q401 is defective or its solder is defective.
• Q402 is defective or its solder is defective.
No IC400 is defective or its solder is
defective.
2
3
No • Connection of CP401 is defective.
• Main transformer is defective.
• Q501 is defective or its solder is defective.
No
• DZ513 is defective or its solder is defective.
• R508 is defective or its solder is defective.
• FPC101 or FPC400 solder is defective.
No
IC101 is defective or its solder is
defective.
No
• FPC101 or FPC400 solder is defective.
• Connection between FPC101 - FPC400 is defective.
SX-20-K
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4
4